Many dike failures have been ignited by damage due to erosion on the landward slopes. This paper investigates how grass covered slopes perform when being attacked by overtopping flow during storm surges. Based on observations during a number of simulator tests, damage is classified into three types 'head-cut', 'roll-up' and 'collapse' depending...

This paper presents adaptations to the XBeach model aimed at including the relevant processes for the generation of scour holes at the toe of a revetment. Dutch assessment rules for the safety of sea defenses need to be adjusted to cope with a combination of sandy dunes and hard elements. To that end, the XBeach model is prepared to be...

Within the framework of WTI, Research and Development of Flood Defence Assessment Tools (Wettelijk Toetsinstrumentarium), which is called in Dutch: WTI-2017 "Onderzoek en ontwikkeling landelijk toetsinstrumentarium", research was carried out to develop an erosion model for grass in the wave run-up zone consistent with the current model in use...

The numerical simulation of wave attack on a sea dike with an asphalt concrete revetment during a severe storm is carried out using the dynamic Finite Element Method. When wave loads attack the revetment during such a storm, both the revetment and the underlying soil may be damaged. The two-phase flow equations are considered, to study the...

In a situation with a narrow dune, the dune base can be protected with a revetment to reduce dune erosion during extreme events. To quantify the effects of a revetment on storm impact, the functionality of the numerical storm impact model XBeach (Roelvink et al., 2009) is extended to account for the complex morphodynamics around revetments. Here...

A revetment of pattern placed elements, or a so called pitching, is used worldwide to protect shorelines and embankments. Also in The Netherlands more than 500 km of river, lake and sea dikes is protected by pitchings. Until the 60’s the design and construction of pitchings was based on experience. After the first damages on pitchings and the...

Apart from many ecological advantages, mangroves in front of a coastal defence may lower the construction and maintenance costs of the defence. Although mangroves have hardly any reducing effect on water levels (and on tsunami impact) mangroves may significantly reduce wave attack on a coastal dike, and in this way reduce the cost of a revetment...

The Hillblock is a concrete element for the protection of dike slopes. Delta Marine Consultants (DMC) investigated the hydraulic properties of the Hillblock in 2D model tests. Wave run-up measurements have been performed on dike slopes with Hillblock revetment and on a smooth impermeable reference slope. The model tests have been carried out at...

Revetments protect the shorelines of coasts, estuaries and rivers against wind wave, ship wave, current and ice attack. The resistance of revetments essentially depends on the properties of the cover layer. The resistance of interlocked pattern placed revetments depends on the weight of the individual stones and the interlocking. Extensive large...

In this manual design rules and guidelines for the design of Polyurethane Bonded Aggregate revetments (PBA-revetments) are presented, based on results from laboratory research, full scale model tests, and experience and field measurements. Research is still ongoing, but from the first results some insight into the structural behaviour of PBA can...